Effects and mechanism of apolipoprotein A5 on adipogenic differentiation of human adipose-derived mesenchymal stem cells

Abstract

Objective To investigate the effect and related mechanism of apolipoprotein A5 (ApoA5) on adipogenic differentiation of human adipose-derived mesenchymal stem cells (AMSC). Methods Subcutaneous adipose tissue was obtained from 40 patients undergoing abdominal surgery at our hospital from February to July 2015. After induction of human AMSC by collagenase digestion, the adipose tissue was induced to differentiate into mature adipocytes and treated with ApoA5 at 600 and 1 200 ng/ml, respectively (ApoA5 intervention groups). Cells treated without ApoA5 protein were used as control group. The cells were harvested on the 7th and 14th day of differentiation, and the following assays were performed: (1) the effect of ApoA5 on TG content was measured by a TG assay kit; (2) RT-qPCR assay was used to detect the effect of ApoA5 on aP2 and FAS mRNA expression; (3) the effect of ApoA5 on the expression of CIDEC mRNA and protein was detected by RT-qPCR and Western blot; (4) the effect of ApoA5 on the expression of C/EBPβ mRNA and protein was detected by RT-qPCR and Western blot; (5) using lentiviral transfection technique, we overexpressed the gene of CIDEC in AMSC and cells were divided into lentiviral negative control group, lentiviral over-expressed CIDEC group and lentiviral over-expressed CIDEC+ApoA5 intervention group (the ApoA5 intervention concentration was 1 200 ng/ml). Thereby, we examined the effect of ApoA5 on the above indicators in adipogenic differentiation of AMSC in the case of CIDEC overexpression. Results (1) Effect of ApoA5 on TG content in AMSC: on the 7th and 14th day after the intervention, the TG levels were lower in ApoA5 600 and 1 200 ng/ml group AMSC than those in the control group (all P 0.05). (6) The effect of ApoA5 on the expression of aP2 and FAS mRNA in AMSC after CIDEC overexpression: on the 7th day after intervention, the expression levels of aP2 and FAS mRNA in AMSC were higher in the lentivirus over-expressed CIDEC group than in the lentivirus negative control group (both P 0.05). (7) The effect of ApoA5 on the expression of C/EBPβ mRNA and protein in AMSC after CIDEC overexpression: on the 7th day after intervention, the mRNA and relative protein expressions of C/EBPβ in AMSC were higher in lentivirus-overexpressed CIDEC group than in lentivirus negative control group (both P 0.05). Conclusions ApoA5 can inhibit the adipogenic differentiation of AMSC,and this effect may be mediated by down-regulating the expression of CIDEC. Furthermore, our results indicate that CIDEC could be considered as a key factor in adipogenic differentiation. Key words: Apolipoproteins A; Adipogenesis; Adipose-derived mesenchymal stem cells